qmk_firmware/keyboards/rgbkb/pan/rev1/proton_c/info.json

{
    "processor": "STM32F303",
    "bootloader": "stm32-dfu",
    "board": "QMK_PROTON_C",
    "encoder": {
        "rotary": [
            {"pin_a": "B14", "pin_b": "B15"},
            {"pin_a": "B11", "pin_b": "B12"}
        ]
    }
}